After Parkland, there have been many calls to make schools a "harder target" — for example, by arming teachers. But there's a decent amount of research out there on what actually makes schools safer, and most of it doesn't point to more guns.

President Trump expressed grief Thursday over the school shooting in Florida and sought to comfort victims and their families in his first public address since the mass killing at Marjory Stoneman Douglas High School left 17 people dead and many others injured.

"To every parent, teacher and child who is hurting so badly, we are here for you whatever you need, whatever we can do to ease your pain," he said.

The Army, Navy, Marines and Air Force all regularly fail to submit required crime data to the FBI for inclusion in national databases, but the Air Force has shown improvement over the past several years, according to a new report released by the Department of Defense Office of the Inspector General.

A 29-year-old man suspected in a shooting incident outside a local store is currently held without bail. Town of Cheektowaga Police, meanwhile, confirmed that two "civilian heroes" intervened and helped officers avert what authorities say could have been a mass shooting.

At about 10:08 p.m. local time Sunday, the first reports of gunfire surfaced on dispatch radio for the Las Vegas Metropolitan Police Department. By about 11:20 p.m., law enforcement had used explosives to bust down the door of a hotel room in Mandalay Bay, where they would soon report their suspect dead, surrounded by firearms.

Police are still trying to determine what motivated Stephen Paddock to rain gunfire on some 22,000 music fans along the Las Vegas Strip on Sunday night. The attack left 59 people dead and more than 500 people were injured, in the worst mass shooting in recent U.S. history.

In an afternoon news conference, Las Vegas Sheriff Joseph Lombardo said that the number of injured, reported at 527 yesterday, has "decreased slightly...maybe 20, because we had a double count error occurring at one of the hospitals."

A state police trooper and a 27-year-old woman were killed Sunday night as part of an apparent domestic violence incident in Jefferson County. Gov. Andrew Cuomo has ordered flags on state buildings flown at half-mast in honor of Trooper Joel Davis.

The FBI says the man who opened fire on a group of Republican members of Congress on Wednesday is 66-year-old James T. Hodgkinson of Belleville, Ill., who was shot by police and later died at a hospital.

The alleged shooter expressed fervent opposition to the Republican Party and called for higher taxes on the rich, in statements on social media and letters to a local newspaper. He apparently volunteered for the presidential campaign of Sen. Bernie Sanders, according to the Vermont senator, who condemned the attack.

Rep. Chris Collins says the shooting of fellow Republicans at a congressional baseball practice Wednesday morning is "a sobering wake-up call." He says as President Donald Trump's "number one surrogate" in Washington, he plans to take added precautions at public gatherings.

House Majority Whip Steve Scalise of Louisiana has undergone surgery and will need further operations, after being shot by a man who opened fire with a rifle on an early morning baseball practice for Republican members of Congress in Alexandria, Va. Scalise was the most seriously injured of four victims of the shootings.